1. Field of the Invention
This invention relates to an ancillary device for dental treatments, and more particularly to a tongue press adapted to a tongue press holder and used for holding in position and protecting the patient's tongue in a dental treatment of the inside of a tooth or teeth on the mandible so that the patient's tongue won't be injured by a treating instrument even when the patient's tongue is moved inadvertently or the dentist's fingers slip or are improperly handled in the patient's month during the treatment.
2. Description of the Prior Art
In dental treatments, high-speed cutting and polishing tools are often used for chipping out or abrading the affected part of a carious tooth.
An important problem in such dental treatments, especially in the treatment of the inside of a tooth or teeth on the mandible, is how to protect the patient's tongue, which is sensible and has a great many of blood vessels therein, from the treating instruments such as cutting and polishing tools.
In fact, it is not rare in the dental treatments that the patient's tongue be injured by a treating instrument which happen to touch the patient's tongue as a result of an inadvertent movement of the tongue or slip of the dentist's fingers in the mouth.
As the protective devices of the type under consideration, there have been proposed an external tongue holder (Japanese Patent Application No. 18936/83) which is adapted externally to the mandible of a patient for fixing his tongue in position in the mouth while covering the upper side of the tongue so as to securely protect the patient's tongue during the treatment, and an internal tongue holder (Japanese Utility Model Application Nos. 153236/82 and 153237/82) similar in principle to said external type but applied interiorly in the oral cavity. These applications have been filed by the same applicant as the present application in Japan.
Referring to the accompanying drawings, FIG. 13 is a perspective view of said external tongue holder adapted with a known type of tongue press, and FIG. 14 is a diagrammatic side view of the mandible of a patient to which the external tongue holder of FIG. 13 has been applied. In these drawings, reference numberal 4 designates the external tongue press holder, 5 a joining member and 6 a lower jaw supporting member.
Said external tongue press holder 4 consists of a tongue press 7 having a central body portion 18 and an integral edge portion 19 designed to cover and hold in position the top, front and both side sections of the tongue 2 at a location near the inner periphery of the lower gingiva 3, said central body portion 18 having a joining protuberance 20 centrally on its upper side; a lower jaw supporting member 6 having a jaw sustaining portion 14 configured in conformity to the contour of the lower jaw 1 and positioned in opposition to said tongue press 7 so as to help to fix the tongue in position in the mouth, a rising portion 15 which rises up substantially vertically from an end of said jaw sustaining portion 14, and a joining portion 17 cranked substantially at right angles from the upper end of said rising portion 15 so that said joining portion 17 is substantially parallel to said jaw sustaining portion 14, said joining portion 17 being formed centrally thereof with a connecting hole 16; and a connecting member 5 having a joining portion 10 formed with holes 9 into one of which is securely fitted the protuberance 20 of said tongue press 7, a curved portion 11 extending from an end of said joining portion 10 with a proper curvature so as to bypass the lower gingiva 3, and a vertical portion 12 extending down vertically from said curved portion 11 (substantially vertically to said joining portion 10), passed through the connecting hole 16 of said supporting member 6 and provided with a stopper 13 at the lower end thereof.
In use of this external tongue press holder 4, first the jaw supporting member 6 is lowered down sufficiently to provide an ample spacing between said tongue press 7 and the jaw sustaining portion 14 of said supporting member 6 and then the tongue press 7 joined integral to the connecting member 5 is placed into the mouth so as to cover and hold down the tongue 2 in position. Then the supporting member 6 is pushed upward, with the hole 16 in said supporting member 5 being kept perpendicular to the vertical portion 12 of the connecting member 5, until the jaw sustaining portion 14 is brought into tight attachment against the jaw. Under this condition, the operator lets go his hold on the device, whereby the joining portion 17 is frictionally secured to the connecting member 5 with a slight slant to the vertical portion 12 of said connecting member 5.
FIG. 15 is a perspective view of a conventional internal tongue press holder, and FIG. 16 is a diagrammatic side view of the mouth of a patient where said internal tongue press holder was properly set in its use position. In the drawings, numeral 21 designates the conventional internal tongue press holder, 22 a tongue press, and 23 an elastic curved portion of the holder.
This internal tongue press holder 21 consists of a tongue press 22 adapted to cover the upper part of the tongue 2 and hold it in position near the inner periphery of the lower gingiva 3 and an elastic curved portion 23 joined at its lower end to said tongue press 22, curved elastically at its middle part toward the pharynx of the patient and having at its upper end a tooth abutment 24 which is attached to the ends of the foreteeth 25.
In use of this internal tongue press holder 22, the patient is asked to open his mouth and the operator inserts the tongue press holder 21 into the patient's mouth while slightly flexing the elastic curved portion 23, placing the tongue press 22 just inside of the lower gingiva 3 so that said tongue press 22 covers the upper part, front part and both sides of the tongue to hold it in position near the inner periphery of the lower gingiva 3. The elastic curved portion 23 is curved toward the pharynx of the patient and the tooth abutment 24 at the upper end thereof is engaged with the foreteeth so that the flexing force of said elastic curved portion 23 is exerted to the press holder 22 to let it hold down the tongue 2 securely in position.
Said both external and internal tongue press holder 4 and 21 were generally satisfactory in protecting the patient's tongue from the treating instruments in the dental treatments, but the tongue press 7, 22 had the problems such as unpleasant feeling of the patient in application of the device, production cost, etc.
FIG. 17 is a top plan view of a conventional tongue press 7, and FIG. 18 is a sectional view taken along the line D--D of FIG. 17.
The conventional tongue press 7 is made of a natural or synthetic rubber material and produced by injection molding or other like means to have a configuration conforming to the tongue shape so as to cover the upper, front and both side parts of the tongue excepting the basal part thereof as illustrated in FIG. 17. On the upper side 18 of said tongue press is provided a protuberance 20 which is to be fitted into a fixing hole 9 formed in the external tongue press holder 4.
Also, as illustrated in FIG. 18, the central body portion 18 and the edge portion 19 of said tongue press 7 differ in thickness so that the upper edge portion 19 has a flexibility to accommodate the individual differences in tongue size and shape.
However, the man's tongue size and shape differ greatly depending on not only age and sex but also individually and only one tongue press can not entirely accommodate such differences in tongue size and shape, so that it was necessary to prepare the tongue presses of various sizes and shapes.
Further, since the conventional tongue press 7 or 22 was flat and smooth at its surface contacting the patient's tongue 2, patient's saliva tended to get in between the tongue 2 and tongue press 7, 22 to give an unpleasant clammy sense to the patient, and also the tongue press 7, 22 would slip on the tongue 2, making it unable to securely hold the tongue 2 in position.
Moreover, the mold for producing a tongue press 7 differing in thickness at its central body portion 18 and edge portion 19 as illustrated in FIG. 18 must be varied in clearance between the cope and drag at its sections corresponding to said central body portion 18 and edge portion 19 of the tongue press, and this, coupled with the necessity of forming the intricate carvatures conforming to the individual tongue size and shape, has made the production of the mold very costly.